Method and apparatus for creating a reconstructive graft

ABSTRACT

A method and apparatus is provided for creating an internal reconstruction tissue graft. Templates may be used to create a multitude of patterns in a variety of tissue reconstruction grafts. An apparatus may be used to create an internal tissue graft for reconstruction through either compression and/or removal of segments. An apparatus may be used, through either compression and or removal of segments of a preformed template made of synthetics and or metal that mirrors a template that can be used as an internal tissue graft for reconstruction. In a method, such as using software analysis and an apparatus, the physical properties of the tissue graft and its pre- and post-operative properties and appearance may be measured.

RELATED APPLICATION DATA

This application is a continuation of U.S. application Ser. No.14/678,188, filed Apr. 3, 2015, which is a continuation-in-part of U.S.application Ser. No. 13/687,082, filed Nov. 28, 2012, now U.S. Pat. No.9,050,177, issued Jun. 9, 2015, which is a continuation of U.S. patentapplication Ser. No. 13/101,022, filed May 4, 2011, now U.S. Pat. No.8,858,647, issued Oct. 14, 2014, and claims priority to U.S. ProvisionalApplication Ser. No. 61/331,805, filed May 5, 2010, the contents of saidearlier applications being incorporated by reference in their entiretyherein.

FIELD OF THE INVENTION

The present invention relates to reconstructive tissue grafts.

BACKGROUND OF THE INVENTION

Current surgical reconstruction of internal tissue defects utilizes asolid, porous sheet with or without perforations. Current grafts allowfor perforations that do enhance fluid egress and in growth of newtissue but due to the constrictive nature of such tissue grafts, theincidences of recurrences and the inability to expand with theapplication of increased pressure has allowed for a significantincidence of recurrence, stress tears, and an inability for expansionused in reconstructive and aesthetic procedures. Current tissue graftsalso do not allow for the ability to enhance traction between the graftand specific anatomic points, similar in physical properties of howspecific tread designs enhance traction between the tire and the roadsurface, as well as increase the time of utilization of the tire. Thecurrent novel invention applies these engineering applications toachieve similar results to internal surgical tissue grafts. None of thereferences below discuss the advantages of utilizing the current methodand apparatus of applying designs and templates to internal surgicalreconstructive grafts.

BRIEF DESCRIPTION OF THE FIGURES

FIGS. 1A and 1B illustrate a top and bottom, respectively, of a tissuegraft having patterns in accordance with the invention;

FIG. 2 is a side view of a tissue graft having various surface patternsin accordance with an embodiment of the invention, which patterns may beused to contain or retain medicants, tissues or other materials inaccordance with other embodiments of the invention;

FIGS. 3A, 3B, and 3C illustrate a method of modifying a tissue graftwith a template to create a modified tissue graft having one or moresurface patterns and associating one or more medicants with said surfacepatterns in accordance with an embodiment of the invention; and

FIGS. 3D and 3E illustrate additional embodiments of a modified tissuegraft in accordance with the invention.

SUMMARY OF THE INVENTION

Various methods and apparatus for creating an internal reconstructiontissue graft are disclosed. Aspects of the invention comprise: 1) amethod for the creation of templates used to create a multitude ofpatterns in a variety of tissue reconstruction grafts; 2) an apparatusthat through either compression and or removal of segments of tissuecreate the internal tissue graft for reconstruction; 3) an apparatusthat through either compression and or removal of segments of apreformed template (such as made of synthetics and or metal) thatmirrors a template that can be used as an internal tissue graft forreconstruction; and/or 4) a method of measuring, through softwareanalysis and an apparatus, the physical properties of the tissue graftand its pre and post-operative properties and appearance.

In one embodiment, a template is used to modify the surface of a tissuegraft to include variable and multiple patterns, creating a modified orreconstructive graft which is configured for incorporation into aparticular anatomic area.

In one embodiment, the invention is configured to, and an advantage ofthe invention comprises, reducing stress in grafts subject to continuousmotion, such as, in the knee, hip, and cervical regions

In one embodiment, the invention is configured to, and an advantage ofthe invention comprises, reducing stress in grafts subject to increasedpressure gradients such as in the abdominal wall, inguinal hernia, andarterial grafts.

In one embodiment, the invention is configured to, and an advantage ofthe invention comprises, allowing for selective expandability (such asvia partial or non-through expansion incisions and/or through expansionincisions of various thicknesses in the graft) in order to achievebetter contour and external appearance.

In one embodiment, the invention is configured to, and an advantage ofthe invention comprises, allowing for selective expandability (such asvia partial or non-through expansion incisions and/or through expansionincisions of various thicknesses in the graft) in order to achievebetter outflow of blood in venous grafts.

In one embodiment, the invention is configured to, and an advantage ofthe invention comprises, allowing for selective traction or adhesionpoints of tissue grafts to key anatomic areas when needed in order toincrease fixation at insertions and origins to reduce slippage of thegraft.

In one embodiment, the invention is configured to, and an advantage ofthe invention comprises, promoting vascular in growth of the body'stissue in specific areas of the internal tissue graft.

In one embodiment, the invention is configured to, and an advantage ofthe invention comprises, allowing for an increase in the period of timeof utilization and longevity of the internal reconstructive graft.

Another embodiment of the invention comprises methods and apparatus forcreating a graft, such as a reconstructive tissue graft, which includesa medicant, such as antibiotics, growth factors, or chemotherapeutics,or other tissues, such as stem cells.

Further objects, features, and advantages of the present invention overthe prior art will become apparent from the detailed description of thedrawings which follows, when considered with the attached figures.

DETAILED DESCRIPTION OF THE INVENTION

Aspects of the invention comprise methods of making one or moretemplates which are usable to modify a tissue graft to create a modifiedtissue graft, such as by cutting or removing portions of the tissuegraft or otherwise create surface patterns or other features; methods ofmodifying a tissue graft to create a modified reconstructive tissuegraft, which reconstructive tissue graft may have features which areselected to address particular objectives relative to a particularanatomical site; and reconstructive grafts, including reconstructivetissue grafts which have features which are designed for particularmedical goals and/or for a particular anatomical site.

One embodiment of the invention comprises a method of creating templatesused to create a multitude of patterns in a variety of tissuereconstruction grafts. Such may consist of pre- or intra-operativelymade templates.

In one embodiment, the templates may be based on an analysis of aparticular anatomical region, such as software analysis of an image ofinitial tissue defect, the template designed to allow for a desiredgraft pattern to reduce the potential pressure, reduce stress, decreasewear and tear, provide traction, or achieve other objectives whenimplanted or placed at a particular anatomical site. Based on factorssuch as, but not limited to, the size, shape, thickness, width,variegations, type, and the desired surgical outcome, a tissue graft maybe modified to include a pattern or other features. Due to thevariability in a defect being reconstructed, such as the abdominal wall,breast, face, and extremities, different template patterns may begenerated. Software analysis may be used to create an appropriateinternal tissue graft for an identified existing defect.

In one embodiment, different materials may be used to make the templatesand their respective patterns. In a preferred embodiment of theinvention, internal reconstruction grafts may be created which not onlypermit mesh expansion, but provide for a multitude of various designs,shapes, patterns, variegations and materials to accommodate the existingdefect to achieve the desired reconstructive and aesthetic results.

In one embodiment, software and/or hardware may be used to perform apre-manufacture or pre-operative analysis. Templates may be constructedfrom a pre-made mold, and be made of different materials such as metalor plastic to be integrated with a compression device. The template canbe integrated with a stationary or portable compression apparatus thatcan create prepackaged tissue grafts in a pre-manufactured configurationby a manufacturer or to be subsequently sterilized and used by a surgeonin the operating room. Alternatively, portable temples and/orcompression devices can be used in a sterile operation room, or anapparatus may allow a surgeon or manufacturer to incise predeterminedpatterns into a tissue graft by a knife or other cutting implement. Aprimary objective of the invention allows for a tissue graft to bemodified to create a reconstructive graft which is patterned to addressor accommodate anticipated problems due to any and all activity andreconstructive and aesthetic results.

In one embodiment, an apparatus, either via compression and/or removalof segments of tissue, creates an internal tissue graft forreconstruction by creating a desired pattern within an internal tissuegraft. Compression can be used against the template that in turn createsthe desired internal pattern.

In a second methodology, pre-designed patterns of tissue mirror thespecific designs on a pre-formed template that can be subsequently usedon a portable compression and punch apparatus that can used to createthe internal tissue graft in the operating room. Additional techniquesusing an apparatus that uses laser cutting technology can be utilized.

For example, FIG. 2 illustrates a tissue graft 20 where compressionand/or removal of segments (such as spaced or separated by variousdistances between them) create recessed expansion patterns of variousdepths and shapes 22, adhesion projections of various heights and shapes24 and through holes 26. FIGS. 1A and 1B illustrate one example ofpatterns of adhesion features 22 and expansion features 24 relative to atop (in FIG. 1A) and bottom (in FIG. 1B) of a tissue graft 20, whichpatterns may be used to generate a tissue graft having particulardesired characteristics for a particular application.

Current medical devices are not applicable for creating the multitude ofdesired pattern grafts for each defect. In accordance with theinvention, an apparatus can be used to create patterns applicable to aspecific tissue defect, whether pre- or intra-operatively.

Measuring, such as through image capture and software analysis, thephysical properties of the reconstructive tissue graft and its pre- andpost-operative appearance may be utilized to correlate the physicalproperties of a created internal tissue graft and desired reconstructiveand aesthetic grafts.

Broadly the present invention is directed to methods, apparatus, anddevices involving variable templates for the purpose of internalreconstruction of body tissues including, but not limited to, a breast,the abdominal wall, vascular, and extremities. In a first method inaccordance with the present invention, a template is created that allowsfor increased flexibility as it relates to the graft, and subsequentlythe need to contouring to sling a breast implant used in achieving anatural result for the patient. The template is pre-made or createdduring the reconstruction procedure to enhance the physical propertiesof the internal tissue graft to meet the requirements of the tissuegrafts expectations, whether it is enhanced expansion, flexibility,traction, or period of utilization in anatomic areas where it is placed.

In one embodiment of the invention, the tissue reconstructive grafts arecomposed of cadaveric human tissue. In other embodiments, the tissuereconstructive grafts may be composed of cellular non-human tissue,including cellular and acellular processed graft. The tissuereconstructive grafts may also be composed of synthetic materials.

The features of the reconstructive tissue grafts, such as created usingthe templates may vary: (1) the designated patterns may vary by thedistance between them and the patterns can be of various shapes, widths,thicknesses, and variegations; the designated patterns or other featurescan be either full thickness or partial thickness of the graft; thedesignated patterns can be on both anterior and posterior surfaces ofthe graft; the designated patterns may be configured to provide enhancedcontrolled expansion of the tissue graft; the designated patterns may beconfigured to provide enhanced stress relief during motion of the tissuegraft; the designated patterns may be configured to provide enhancedadhesion between the tissue graft and anatomic region; the designatedpatterns may be configured to provide enhanced retention of variousmedicants and materials both in vitro and in vivo; the designatedpatterns may be configured to provide enhanced longevity and utilizationof the graft.

Templates or other apparatus which are used to modify a tissue graft tocreate a modified reconstructive tissue graft may be made of a varietyof materials, including synthetics, plastic, and metals; the templatesor other apparatus may be used in a manufacturing facility or operatingroom; the templates or other apparatus may be operable by manualpressure, air pressure, hydraulic pressure, or electrically drivenapparatus such as motor driven presses or screws, including via aportable compression device.

As indicated herein, the reconstructive graft may include varioussurface or other features, including for enhancing the retention ofmedicants or other materials (unless otherwise indicated, the term“medicants” as used herein may include medicants, tissues or othermaterials, as described below). In one embodiment, for example, surfacefeatures such as projections, channels, depressions, voids, pockets orthe like may be formed in or through the tissue graft for accepting oneor more medicants (including but not limited to chemotherapeutics,antibiotics, growth factors or other drugs), other tissues (includinghuman non-human tissue, synthetic tissue, stems cells or the like) orother materials such as rebar (or other supportive or strengtheningmaterials). In one embodiment, the reconstructive tissue graft may bepre-created with such features and then the medicants, other tissues ormaterials may be associated with the reconstructive tissue graft at alater time, such as before or during surgery. In other embodiments, areconstructive tissue graft may have such materials pre-associated. Forexample, a tissue graft may be modified by forming one or more pockets,sleeves, folds, voids or the like, and one or more medicants, tissues orother materials may be associated with those pockets or voids duringmanufacture. The pre-configured, pre-medicated reconstructive tissuegraft may then be provided to the surgeon for use. It will beappreciated that while medicants may be associated with a reconstructivetissue graft, other materials might also be associated, such as othertypes of tissue (as described above), bone material, or even metalmeshes, or a variety of other materials (such as depending upon theparticular anatomical region and/or condition for which thereconstructive tissue graft is intended).

The templates of the invention and/or other apparatus may be used toplace such medicants or other materials. For example, one template maybe used to modify the tissue graft, such as by creating the surfacepatterns, while other apparatus or devices may be used to associate themedicants or other materials (such as a medicant implanter, etc). Inother embodiments, these functions may be combined (such as by havingthe template modify the graft and place the medicants or other materialsor facilitate their placement by associated apparatus).

For example, FIG. 3A illustrates use of a template 120 to modify atissue graft 122, such as by using the template 120 to cut or removeportions of a surface of the graft 122. As illustrated in FIG. 3B, thetemplate 120 or another device may be used to associate a medicant 124(or other material such as tissue, as described above) with one or moreof the created surface features. FIG. 3C illustrates one embodiment of amodified graft 122 which includes one or more surface features and anassociated medicant 124. This pre-prepared modified graft 122 may thenbe located in a particular anatomical area of a patient.

FIG. 3D illustrates another embodiment of a modified graft 222 inaccordance with the invention. As illustrated, the modified graft 222may include one or more surface modifications, such as slots 230 whichfacilitate controlled expansion of the modified graft, such as describedabove. The modified graft 222 might, in addition or alternatively,include one or more features 232 which retain medicants. In oneembodiment, the medicant retaining features are configured toevenly/spacially distribute the associated medicants. As illustrated,this may be accomplished by evenly distributed medicant retainingfeatures. However, as one aspect of the invention, the medicantretaining features may have varying sizes or locations which areconfigured to cause associated medicants to be distributed in othercontrolled fashions (such as accounting for factors such as theconfiguration of the modified tissue graft, including varying thicknessthereof, and anatomical features where the graft is to be placed, suchas higher or lower blood flow in regions adjacent to the graft whenimplanted).

As illustrated in FIG. 2, modification of the tissue graft 20 to includeone or more surface features results in a modified tissue graft whichhas a greater effective surface area than the original unmodified graft.In particular, as illustrated in FIG. 2, the created recesses, holes andthe like have a surface area which is greater than the originalunaltered surface area of the graft 20, thus causing the modified tissuegraft to have an increased surface area which allows a greater amount ofmedicant or other secondary material to be associated therewith, asdescribed herein. Aside from this, other features may have other oradditional benefits. For example, FIG. 3E illustrates different medicantretaining features. As one example, a medicant retaining feature maycomprise or include a void, such as a bulbous cavity 300 formed in thetissue graft. As another example, the feature might comprise a void orcavity which includes a valve 302. The valve 302 may be used to retainthe medicants in the graft during placement and/or control the flow orrelease of medicant or other materials from the associated cavity to theexterior of the graft). The valve 302 might, for example, be formed of aportion of the tissue graft itself, such as an upper layer of the tissuegraft which is perforated or slit. As yet another example, the featuremight comprise a punch-type feature 304 which includes one or morevoids, cavities, pockets or the like which can be used to retainmedicants. Of course, as indicated herein, the size and shape of themedicant retaining features may vary.

In one embodiment, the medicant retaining feature is intended to retainone or more medicants (or other materials, as described herein) forrelease once the tissue graft is located at the desired anatomical site.In other embodiments, the retaining feature might retain the medicant orother material once the graft is placed. For example, a synthetic meshmaterial which is located in the graft may remain in the graft after itis placed, thus strengthening the graft and/or the integration of thegraft with the anatomical site.

The above description represents one embodiment of the presentinvention. However, many variations to the method and apparatus arepossible without deviating from the scope of the invention. It will beunderstood that the above described arrangements of apparatus and themethod described herein are merely illustrative of applications of theprinciples of this invention and many other embodiments andmodifications may be made without departing from the spirit and scope ofthe invention as defined in the claims.

What is claimed is:
 1. A reconstructive tissue graft for placement at ananatomical site of a human, said reconstructive tissue graft prepared bya process comprising the steps of: modifying an exterior surface of atissue graft obtained from a site other than said anatomical site toinclude one or more designed surface features, said designed surfacefeatures comprising one or more openings; and associating at least onemedicant, secondary tissue or other material with one or more of saiddesigned surface features comprising at least partially filling said oneor more openings.
 2. The reconstructive tissue graft in accordance withclaim 1 wherein said tissue graft comprises human tissue.
 3. Thereconstructive tissue graft in accordance with claim 2 wherein saidhuman tissue comprises soft, non-bone, tissue.
 4. The reconstructivetissue graft in accordance with claim 1 wherein said at least onemedicant comprises one or more of an antibiotic, a hormone, a growthfactor and a chemotherapeutic agent.
 5. The reconstructive tissue graftin accordance with claim 1 wherein said other material comprises one ormore of acellular human tissue, non-human tissue, stem cells and atleast one synthetic material.
 6. The reconstructive tissue graft inaccordance with claim 1 wherein said one or more designed surfacefeatures comprise one or more voids, pockets, sleeves, channels,depressions, projections and folds at said exterior surface of saidtissue graft.
 7. The reconstructive tissue graft in accordance withclaim 1 wherein said step of modifying comprises removing material fromone or more areas of said exterior surface of said tissue graft.
 8. Thereconstructive tissue graft in accordance with claim 7 wherein said stepof removing comprises or more of cutting and punching.
 9. Areconstructive tissue graft for placement at an anatomical site of ahuman, said reconstructive tissue graft prepared by a process comprisingthe steps of: modifying an exterior surface of a tissue graft having afirst surface area, said tissue graft obtained from a site other thansaid anatomical site to include one or more designed surface features,said designed surface features causing said tissue graft to have asecond increased surface area which is greater than said first surfacearea, one or more of said designed surface features comprising pocketscreated by punching material from said tissue graft; and associating atleast one medicant, secondary tissue or other material with at least aportion of said exterior surface of said tissue graft which includes oneor more of said designed surface features.
 10. The reconstructive tissuegraft in accordance with claim 9 wherein said one or more designedsurface feature comprise one or more pockets extending into saidexterior surface of said tissue graft.